How to run Android hidden codes on a tablet

I have a Galaxy Tab 2 but it has no directly accessible Phone app. But it does appear in App manager though.

In need to run android codes such as: *#*#526#*#* to reinstall a wifi driver, how can I run these sort of codes without dialing them in the Phone app?

Is there any other way to run these sort of codes, or a method to bring up the Phone app? If a tablet like this doesn't offer a Phone app to dial, does this mean mainentance code/tool access is blocked by that means?